SilverLight 5 and VS2019 - missing assembly reference?

Question

I have a SilverLight app and I'm trying to make it work with VS2019 and .NET 4.7.2, SilverLight - 5.0

I get following error while compiling:

Error   CS0234  The type or namespace name 'TabItem' does not exist in the namespace 'System.Windows.Controls' (are you missing an assembly reference?) 

How to fix this?

I tried to add reference to System.Windows.Controls from framework, but it doesn't exist, in order to support SilverLight in VS2019 i use this extension:

https://marketplace.visualstudio.com/items?itemName=RamiAbughazaleh.SilverlightProjectSystem

Answer 1

Install the Silverlight Toolkit

Silverlight 5 Toolkit December 2011.1

Silverlight Toolkit on GitHub

Answer 2

Silverlight stopped being officially supported in VS2017, you should use VS2015 instead.

This is detailed in the VS2017 compatibility notes here

If you are using an plugin to make this work in 2019 I would recommend contacting the plugin owner for assistance.